GRP roof leaks at expansion joints

[Triassic]

A mate has a flattish GRP cover roof, around 3.5m top to bottom and 20m in breadth. It’s started to leak at a couple of the roll top expansion joints. He had them recovered with more GRP and  12 months down the line they leak again. Is there something a bit more flexible he could try to seal them with? Suggestions?

[SteamyTea]

2 hours ago, Triassic said:

Suggestions

Crystic D8151.

It is a flexible polyester resin.

Can be used on its own or mixed in with other resins.

Also, rather than chopped strand mat, a unidirectional weave can be used.

[Conor]

Don't have it to hand but my GRP supplier supplied a silicone type stuff in tubes for movement areas. Used it where deck abutted steel and would be thermal movement. Stuck trim over the junctions and top coat over. No issues so far.

[Triassic]

13 hours ago, Conor said:

Don't have it to hand but my GRP supplier supplied a silicone type stuff in tubes for movement areas. Used it where deck abutted steel and would be thermal movement. Stuck trim over the junctions and top coat over. No issues so far.

That sounds good, any idea what it’s called.

[saveasteading]

20m is probably too long, so it is not moving with temperature. 

Try the suggestions above but expect to repeat before long. Hence use the best material, at maybe 3 x the price.

Is it UV resistan? You would hope they jad thoight about it.

Don't trust what they say on cheap stuff. You need uv proof and lots of elasticity.

[scottishjohn]

yuo got a picture of the installation?

moore liley to be the edge flashing 

and its running under the expasnion joints and showing away from actual leak point